Add iteration quickaction displays ID format on autocomplete

We already support assigning an iteration via quickactions
by name or ID. This change simply adds the ID syntax
to the quickaction autocomplete

Changelog: added
EE: true

ee/lib/ee/gitlab/quick_actions/issue_actions.rb

@@ -75,7 +75,7 @@ module IssueActions
           execution_message do |iteration|
             _("Set the iteration to %{iteration_reference}.") % { iteration_reference: iteration.to_reference } if iteration
           end
-          params '*iteration:"iteration name"'
+          params '*iteration:"iteration name" | *iteration:<ID>'
           types Issue
           condition do
             quick_action_target.supports_iterations? &&